The effects of refrigerated storage of raw milk on the quality of whole milk powder stored for different periods

Whole milk powders were produced from fresh (control) and stored (4 ± 1 °C, 48 ± 2h) raw milk in three seasons (spring, summer and autumn), and stored for up to 8 months at 25 ± 1 °C. The suitability of the milk powders for reconstitution processes was assessed on the basis of selected microbiological, physical, chemical and biochemical quality parameters. Storage of raw milk did not significantly affect total bacterial count (TPC) in the resultant powder. Free fatty acid (FFA) content in powder manufactured from stored raw milk was greater than that from the control. TPC and free fat content decreased while insolubility index, FFA and peroxide value increased during storage of powder; lipase and proteinase activities did not change. All powders manufactured from control and stored raw milk, and stored for up to 8 months, were found suitable for reconstitution on the basis of TPC, moisture content and amount of scorched particles but not based on insolubility index.